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Section 3. sample cr23x program – Campbell Scientific Bowen Ratio Instrumentation User Manual

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Section 3. Sample CR23X Program

The example program is available on the Campbell Scientific FTP site,
ftp://ftp.campbellsci.com/pub/outgoing/files/br_023a.exe. The example
program measures the standard Bowen ratio inputs: vapor pressure and air
temperature gradients, net radiation, and soil heat flux (flux at 8 cm and change
in temperature of the soil layer above). If additional measurements are to be
made or if a different installation is to be used, the program will have to be
altered. Note that even if this exact installation is used, the correct calibration
(multiplier and offset) must be entered for the net radiometer and soil heat flux
plates.

Table 3-1 is a flow chart of the example program and Table 3-2 lists the output
generated by the program.

Power to the pump and cooled mirror is switched on and off by the datalogger.
This can be under manual control by setting a flag in the *6 Mode (flag 6 to
turn on, flag 7 to turn off)
, or automatically by the program if the battery
voltage drops below 11.5 volts (subroutine 2).